1. Field of the Invention
The present invention relates to a technology for transaction distribution.
2. Description of the Related Art
In conventional distributed transaction processing, when one transaction is to be processed, it is necessary to access a plurality of databases, and two-phase commit is used to ensure consistency between databases.
In the two-phase commit, commit processing is divided into two phases. It is checked in the first phase whether the commit has been prepared in databases (prepare phase), and the commit is executed in the second phase only when it is checked that the commit has been prepared in all the databases. In any other cases, rollback is performed in the second phase to ensure consistency between the databases. Reference may be had to, for example, “Let's try distributed transaction!” [Searched on Oct. 12, 2004], Internet<URL: HYPERLINK “http://www.microsoft.com/japan/enable/training/kblight/t00 4/7/01.htm”http://www.ogisri.co.jp/otc/hiroba/technical/DTP/step2>.
In the two-phase commit, however, because the commit processing is performed in the two phases, the processing is inefficiently performed. Moreover, when a failure occurs in a computer that executes a transaction manager for managing distributed transaction processing, a transaction log is required that the transaction manager uses for recovery processing. A burden of introduction and management of the transaction log is substantial.